Focusing attachment for folding cameras



Oct. 2, 1923. v F. TORKA ET AL ydousme ATTACHMENT FOR FOLDING CAMERAS Filed Nov. 15 1920 2 Sheets-Sheet 1 I I autumn: M 222161 ,7

Oct. 2 1923. 1,469,547

k F. TORKA ET AL FOCUSING ATTACHMENT FOR FOLDING CAMERAS Filed Nov. 13 192C! 2 Sheets-Sheet 2 I zxuunlnts flank 2 07M r" dJEedda-v Patented Oct. 2, 1923.

NITED STATES PATENT OFFICE.

FRANK TOEKA AND PAUL H. C. BEDDERS, OI PORT TOWNSEND, WASHINGTON, AS-

SIGNOBS TO PORT TOWNSEND CAMERA 00., 01 PORT TOWNSEND, WASHINGTON,

A CORPORATION 01 WASHINGTON.

I'OCUSING ATTACHMENT FOB FOLDING CAMERAS.

Application ma November 13, 1920. Serial so. macro.

To all whomit may concern:

Be it known that we, FRANK Toxm and PAUL H. C. Reopens, citizens of the United States, residing at Port Townsend, in the county of Jefferson and State of Washington, have invented certain new and useful Improvements in Focusing Attachments for Foldin Cameras; and we do hereby declare the folIo enable others skilled in the art to which it appertains to make and use the samel This invention relates to focusing devices for cameras and more'particularly to focusing devices for folding or collapsible cameras. I p The object of the invention is to provide a substantially accurate focusing device capable of being used with a collapsible or foldable camera, and with means for operating such a focusing device simultaneously and in proper'ratio with the lens of the camera itself.

Other objects will appear and be explained more particularly in connection with the detailed description hereinafter.

The invention consists in certain novel structures, arrangements and combinations of parts hereinafter more particularly do 0 scribed and claimed.

Two sheets of drawings aooompan this specification as part thereof in whic "like reference characters denote like parts throughout.

Figure 1 is a plan view of a folding camera in its ppen position showing one form of the improved focusing device; Fi re 2 is a similar view with the camera lens older only artially extended; I

Figure 3 is a etail view of the front end of the camera door showing the supporting carriage for the camera lens partly in section;

Figure 4 is a transverse'sectional view taken on the line 44 of Figure 3;

5 is a side elevation of Fi re 1;

Figure 6 is a view similar to iglire 3 showing a modified form of the device;

Figures 7 and 8 are detail views of modified forms of the device. I

Referring to the drawin 1 indicates the body of the camera. 2 in icates the hinged front or door of the camera. 3indicates the camera or service lens holder. 4 indicates the ordina wing to be a full clear, and exact 10 description of the invention, such as will and well known finder. 5 indicates trac s fixed to the door'2 upon which service lens holder 3 is adapted toslide.

which is old and well known, it is proposed -to apply a focusing device which consists of a focusm lens 6 carried in'the member 6, which is adapted to fit over the end of a tubular member 7 which in turn slidably telescopes overa tubular member 8.; The rear end of tubular member 8 communicates with box 9 within which are mounted a suitable reflector such as mirror 10, and an image receiver such as ground glass screen 10'. The member 9 is fixedly'secured' to the door 2 b means of screws 24 while tubular member is connected by means of a lip 11 and screw To the device thus far described, all of 12 to a lever arm 16 pivoted as at 20 and provided with slots 18 and 19. -This lever arm 16 extends transversely across the door 2 passing through suitable slots in the tracks 5 so that it operates beneath the upper surfaces of and between the tracks. On the under carriage 13 ofthelens holder 3 of the camera, there is rovided a vertically adjustable screw 15 a apt ed to cooperate with the lever 16 through slot 18 so that, upon swinging lever 16 upon its pivot 20, focusing lens 6 and camera lens 3 will be moved forward .or backward'as may be desired, but alwa s 1 in apredetermined ratio determined by t e distances between the pivot 20 and the respective points of connection of said lensto the lever. By elevating the screw 15 it can be made to entirely clear the slot,18 in the lever 16 so that the lens carrier of the camera can be folded up leaving the focusing device and the operating lever in proper position on the cover 2. In order to make the differences-in focusingdistinguishable to the human eye it is necessary that the focusing lens shall have at least a three inch focus and it is desirable if possible tduse a five inch focus. In practiceit is-found desirable to use a focusinglens havin two thirds the focus of the camera lens as t islends itself to proper adjustment by means of a lever arm as lllllS- trated. I

Where the space is limited the focusing device may be constructed with a totally re-- fiecting prism or a mirror set at an angle as at 10, and a collapsible extension supportin the image receiver which may be'made eit er with telescoping sections 9 as shown I in Figure 7, or hinged and capable of being folded down, as at 9" in Figure 8.

A modification of the proportional lever device is illustrated in Figure 6 in which the lever terminates at 29 at the end of the slot 18 and the camera lens carriage is operated by means of a rod 25 carrying a pinion 26 coacting with a rack 27, rod 25 being suitabl journaled in the carriage 13.

ther modifications will readily suggest themselves to those skilled in the art.

Having described our invention, what we claim is:

1. A collapsible camera having a hinged front and a lens holder adjustable longitudinally of said hinged front in its open position, a lever pivoted adjacent one side of the hinged front near the forward edge thereof, and a focusing device having an image receiving screen, fixed to the camera front, a fixed tubular member extending therefrom, a second tubular member slidable upon said first member carrying a focusing lens, means carried by said slidablc tubular member for engaging the lever,'means carried by the camera lens carriage for engaging the lever, the distances between the pivot of said lever and the engaging points for connection with said focusing device and camera lens carriage being proportioned in a predetermined ratio.

2. In a collapsible camera having an adjustable lens, a focusing device comprising an adjustable focusing lens, a part fixed to the camera, a collapsible extension to said fixed part carrying an image receiving screen, means for refiectin an image from said focusing lens onto Sfll( receivin screen through said collapsible part, and means for concurrently and proportionately adjusting the camera lens and focusing lens.

3. In a collapsiblefcamera in combination with an adjustable camera lens holder, an adjustable focusing lens, a part fixed to the camera, a collapsible extension to said fixed part carrying an image receiving screen, means for reflecting an image from the focusing lens onto the receiving screen and means for concurrently and proportionately adi'usting the focusing lens and camera lens.

n testimony whereof we aflix'our signatures.

FRANK TORKA.

PAUL H. C. REDDERS. 

